| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/fs.h> |
| #include <linux/loop.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <sys/file.h> |
| #include <sys/ioctl.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "btrfs-util.h" |
| #include "chattr-util.h" |
| #include "copy.h" |
| #include "dirent-util.h" |
| #include "dissect-image.h" |
| #include "env-file.h" |
| #include "env-util.h" |
| #include "fd-util.h" |
| #include "fs-util.h" |
| #include "hashmap.h" |
| #include "hostname-util.h" |
| #include "id128-util.h" |
| #include "lockfile-util.h" |
| #include "log.h" |
| #include "loop-util.h" |
| #include "machine-image.h" |
| #include "macro.h" |
| #include "mkdir.h" |
| #include "nulstr-util.h" |
| #include "os-util.h" |
| #include "path-util.h" |
| #include "rm-rf.h" |
| #include "string-table.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "time-util.h" |
| #include "utf8.h" |
| #include "xattr-util.h" |
| |
| static const char* const image_search_path[_IMAGE_CLASS_MAX] = { |
| [IMAGE_MACHINE] = "/etc/machines\0" /* only place symlinks here */ |
| "/run/machines\0" /* and here too */ |
| "/var/lib/machines\0" /* the main place for images */ |
| "/var/lib/container\0" /* legacy */ |
| "/usr/local/lib/machines\0" |
| "/usr/lib/machines\0", |
| |
| [IMAGE_PORTABLE] = "/etc/portables\0" /* only place symlinks here */ |
| "/run/portables\0" /* and here too */ |
| "/var/lib/portables\0" /* the main place for images */ |
| "/usr/local/lib/portables\0" |
| "/usr/lib/portables\0", |
| }; |
| |
| static Image *image_free(Image *i) { |
| assert(i); |
| |
| free(i->name); |
| free(i->path); |
| |
| free(i->hostname); |
| strv_free(i->machine_info); |
| strv_free(i->os_release); |
| |
| return mfree(i); |
| } |
| |
| DEFINE_TRIVIAL_REF_UNREF_FUNC(Image, image, image_free); |
| DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(image_hash_ops, char, string_hash_func, string_compare_func, |
| Image, image_unref); |
| |
| static char **image_settings_path(Image *image) { |
| _cleanup_strv_free_ char **l = NULL; |
| const char *fn, *s; |
| unsigned i = 0; |
| |
| assert(image); |
| |
| l = new0(char*, 4); |
| if (!l) |
| return NULL; |
| |
| fn = strjoina(image->name, ".nspawn"); |
| |
| FOREACH_STRING(s, "/etc/systemd/nspawn", "/run/systemd/nspawn") { |
| l[i] = path_join(s, fn); |
| if (!l[i]) |
| return NULL; |
| |
| i++; |
| } |
| |
| l[i] = file_in_same_dir(image->path, fn); |
| if (!l[i]) |
| return NULL; |
| |
| return TAKE_PTR(l); |
| } |
| |
| static char *image_roothash_path(Image *image) { |
| const char *fn; |
| |
| assert(image); |
| |
| fn = strjoina(image->name, ".roothash"); |
| |
| return file_in_same_dir(image->path, fn); |
| } |
| |
| static int image_new( |
| ImageType t, |
| const char *pretty, |
| const char *path, |
| const char *filename, |
| bool read_only, |
| usec_t crtime, |
| usec_t mtime, |
| Image **ret) { |
| |
| _cleanup_(image_unrefp) Image *i = NULL; |
| |
| assert(t >= 0); |
| assert(t < _IMAGE_TYPE_MAX); |
| assert(pretty); |
| assert(filename); |
| assert(ret); |
| |
| i = new0(Image, 1); |
| if (!i) |
| return -ENOMEM; |
| |
| i->n_ref = 1; |
| i->type = t; |
| i->read_only = read_only; |
| i->crtime = crtime; |
| i->mtime = mtime; |
| i->usage = i->usage_exclusive = (uint64_t) -1; |
| i->limit = i->limit_exclusive = (uint64_t) -1; |
| |
| i->name = strdup(pretty); |
| if (!i->name) |
| return -ENOMEM; |
| |
| i->path = path_join(path, filename); |
| if (!i->path) |
| return -ENOMEM; |
| |
| path_simplify(i->path, false); |
| |
| *ret = TAKE_PTR(i); |
| |
| return 0; |
| } |
| |
| static int extract_pretty(const char *path, const char *suffix, char **ret) { |
| _cleanup_free_ char *name = NULL; |
| const char *p; |
| size_t n; |
| |
| assert(path); |
| assert(ret); |
| |
| p = last_path_component(path); |
| n = strcspn(p, "/"); |
| |
| name = strndup(p, n); |
| if (!name) |
| return -ENOMEM; |
| |
| if (suffix) { |
| char *e; |
| |
| e = endswith(name, suffix); |
| if (!e) |
| return -EINVAL; |
| |
| *e = 0; |
| } |
| |
| if (!image_name_is_valid(name)) |
| return -EINVAL; |
| |
| *ret = TAKE_PTR(name); |
| return 0; |
| } |
| |
| static int image_make( |
| const char *pretty, |
| int dfd, |
| const char *path, |
| const char *filename, |
| const struct stat *st, |
| Image **ret) { |
| |
| _cleanup_free_ char *pretty_buffer = NULL, *parent = NULL; |
| struct stat stbuf; |
| bool read_only; |
| int r; |
| |
| assert(dfd >= 0 || dfd == AT_FDCWD); |
| assert(path || dfd == AT_FDCWD); |
| assert(filename); |
| |
| /* We explicitly *do* follow symlinks here, since we want to allow symlinking trees, raw files and block |
| * devices into /var/lib/machines/, and treat them normally. |
| * |
| * This function returns -ENOENT if we can't find the image after all, and -EMEDIUMTYPE if it's not a file we |
| * recognize. */ |
| |
| if (!st) { |
| if (fstatat(dfd, filename, &stbuf, 0) < 0) |
| return -errno; |
| |
| st = &stbuf; |
| } |
| |
| if (!path) { |
| if (dfd == AT_FDCWD) |
| (void) safe_getcwd(&parent); |
| else |
| (void) fd_get_path(dfd, &parent); |
| } |
| |
| read_only = |
| (path && path_startswith(path, "/usr")) || |
| (faccessat(dfd, filename, W_OK, AT_EACCESS) < 0 && errno == EROFS); |
| |
| if (S_ISDIR(st->st_mode)) { |
| _cleanup_close_ int fd = -1; |
| unsigned file_attr = 0; |
| |
| if (!ret) |
| return 0; |
| |
| if (!pretty) { |
| r = extract_pretty(filename, NULL, &pretty_buffer); |
| if (r < 0) |
| return r; |
| |
| pretty = pretty_buffer; |
| } |
| |
| fd = openat(dfd, filename, O_CLOEXEC|O_NOCTTY|O_DIRECTORY); |
| if (fd < 0) |
| return -errno; |
| |
| /* btrfs subvolumes have inode 256 */ |
| if (st->st_ino == 256) { |
| |
| r = btrfs_is_filesystem(fd); |
| if (r < 0) |
| return r; |
| if (r) { |
| BtrfsSubvolInfo info; |
| |
| /* It's a btrfs subvolume */ |
| |
| r = btrfs_subvol_get_info_fd(fd, 0, &info); |
| if (r < 0) |
| return r; |
| |
| r = image_new(IMAGE_SUBVOLUME, |
| pretty, |
| path, |
| filename, |
| info.read_only || read_only, |
| info.otime, |
| 0, |
| ret); |
| if (r < 0) |
| return r; |
| |
| if (btrfs_quota_scan_ongoing(fd) == 0) { |
| BtrfsQuotaInfo quota; |
| |
| r = btrfs_subvol_get_subtree_quota_fd(fd, 0, "a); |
| if (r >= 0) { |
| (*ret)->usage = quota.referenced; |
| (*ret)->usage_exclusive = quota.exclusive; |
| |
| (*ret)->limit = quota.referenced_max; |
| (*ret)->limit_exclusive = quota.exclusive_max; |
| } |
| } |
| |
| return 0; |
| } |
| } |
| |
| /* If the IMMUTABLE bit is set, we consider the |
| * directory read-only. Since the ioctl is not |
| * supported everywhere we ignore failures. */ |
| (void) read_attr_fd(fd, &file_attr); |
| |
| /* It's just a normal directory. */ |
| r = image_new(IMAGE_DIRECTORY, |
| pretty, |
| path, |
| filename, |
| read_only || (file_attr & FS_IMMUTABLE_FL), |
| 0, |
| 0, |
| ret); |
| if (r < 0) |
| return r; |
| |
| return 0; |
| |
| } else if (S_ISREG(st->st_mode) && endswith(filename, ".raw")) { |
| usec_t crtime = 0; |
| |
| /* It's a RAW disk image */ |
| |
| if (!ret) |
| return 0; |
| |
| (void) fd_getcrtime_at(dfd, filename, &crtime, 0); |
| |
| if (!pretty) { |
| r = extract_pretty(filename, ".raw", &pretty_buffer); |
| if (r < 0) |
| return r; |
| |
| pretty = pretty_buffer; |
| } |
| |
| r = image_new(IMAGE_RAW, |
| pretty, |
| path, |
| filename, |
| !(st->st_mode & 0222) || read_only, |
| crtime, |
| timespec_load(&st->st_mtim), |
| ret); |
| if (r < 0) |
| return r; |
| |
| (*ret)->usage = (*ret)->usage_exclusive = st->st_blocks * 512; |
| (*ret)->limit = (*ret)->limit_exclusive = st->st_size; |
| |
| return 0; |
| |
| } else if (S_ISBLK(st->st_mode)) { |
| _cleanup_close_ int block_fd = -1; |
| uint64_t size = UINT64_MAX; |
| |
| /* A block device */ |
| |
| if (!ret) |
| return 0; |
| |
| if (!pretty) { |
| r = extract_pretty(filename, NULL, &pretty_buffer); |
| if (r < 0) |
| return r; |
| |
| pretty = pretty_buffer; |
| } |
| |
| block_fd = openat(dfd, filename, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); |
| if (block_fd < 0) |
| log_debug_errno(errno, "Failed to open block device %s/%s, ignoring: %m", path ?: strnull(parent), filename); |
| else { |
| /* Refresh stat data after opening the node */ |
| if (fstat(block_fd, &stbuf) < 0) |
| return -errno; |
| st = &stbuf; |
| |
| if (!S_ISBLK(st->st_mode)) /* Verify that what we opened is actually what we think it is */ |
| return -ENOTTY; |
| |
| if (!read_only) { |
| int state = 0; |
| |
| if (ioctl(block_fd, BLKROGET, &state) < 0) |
| log_debug_errno(errno, "Failed to issue BLKROGET on device %s/%s, ignoring: %m", path ?: strnull(parent), filename); |
| else if (state) |
| read_only = true; |
| } |
| |
| if (ioctl(block_fd, BLKGETSIZE64, &size) < 0) |
| log_debug_errno(errno, "Failed to issue BLKGETSIZE64 on device %s/%s, ignoring: %m", path ?: strnull(parent), filename); |
| |
| block_fd = safe_close(block_fd); |
| } |
| |
| r = image_new(IMAGE_BLOCK, |
| pretty, |
| path, |
| filename, |
| !(st->st_mode & 0222) || read_only, |
| 0, |
| 0, |
| ret); |
| if (r < 0) |
| return r; |
| |
| if (!IN_SET(size, 0, UINT64_MAX)) |
| (*ret)->usage = (*ret)->usage_exclusive = (*ret)->limit = (*ret)->limit_exclusive = size; |
| |
| return 0; |
| } |
| |
| return -EMEDIUMTYPE; |
| } |
| |
| int image_find(ImageClass class, const char *name, Image **ret) { |
| const char *path; |
| int r; |
| |
| assert(class >= 0); |
| assert(class < _IMAGE_CLASS_MAX); |
| assert(name); |
| |
| /* There are no images with invalid names */ |
| if (!image_name_is_valid(name)) |
| return -ENOENT; |
| |
| NULSTR_FOREACH(path, image_search_path[class]) { |
| _cleanup_closedir_ DIR *d = NULL; |
| struct stat st; |
| |
| d = opendir(path); |
| if (!d) { |
| if (errno == ENOENT) |
| continue; |
| |
| return -errno; |
| } |
| |
| /* As mentioned above, we follow symlinks on this fstatat(), because we want to permit people to |
| * symlink block devices into the search path */ |
| if (fstatat(dirfd(d), name, &st, 0) < 0) { |
| _cleanup_free_ char *raw = NULL; |
| |
| if (errno != ENOENT) |
| return -errno; |
| |
| raw = strjoin(name, ".raw"); |
| if (!raw) |
| return -ENOMEM; |
| |
| if (fstatat(dirfd(d), raw, &st, 0) < 0) { |
| |
| if (errno == ENOENT) |
| continue; |
| |
| return -errno; |
| } |
| |
| if (!S_ISREG(st.st_mode)) |
| continue; |
| |
| r = image_make(name, dirfd(d), path, raw, &st, ret); |
| |
| } else { |
| if (!S_ISDIR(st.st_mode) && !S_ISBLK(st.st_mode)) |
| continue; |
| |
| r = image_make(name, dirfd(d), path, name, &st, ret); |
| } |
| if (IN_SET(r, -ENOENT, -EMEDIUMTYPE)) |
| continue; |
| if (r < 0) |
| return r; |
| |
| if (ret) |
| (*ret)->discoverable = true; |
| |
| return 1; |
| } |
| |
| if (class == IMAGE_MACHINE && streq(name, ".host")) { |
| r = image_make(".host", AT_FDCWD, NULL, "/", NULL, ret); |
| if (r < 0) |
| return r; |
| |
| if (ret) |
| (*ret)->discoverable = true; |
| |
| return r; |
| } |
| |
| return -ENOENT; |
| }; |
| |
| int image_from_path(const char *path, Image **ret) { |
| |
| /* Note that we don't set the 'discoverable' field of the returned object, because we don't check here whether |
| * the image is in the image search path. And if it is we don't know if the path we used is actually not |
| * overridden by another, different image earlier in the search path */ |
| |
| if (path_equal(path, "/")) |
| return image_make(".host", AT_FDCWD, NULL, "/", NULL, ret); |
| |
| return image_make(NULL, AT_FDCWD, NULL, path, NULL, ret); |
| } |
| |
| int image_find_harder(ImageClass class, const char *name_or_path, Image **ret) { |
| if (image_name_is_valid(name_or_path)) |
| return image_find(class, name_or_path, ret); |
| |
| return image_from_path(name_or_path, ret); |
| } |
| |
| int image_discover(ImageClass class, Hashmap *h) { |
| const char *path; |
| int r; |
| |
| assert(class >= 0); |
| assert(class < _IMAGE_CLASS_MAX); |
| assert(h); |
| |
| NULSTR_FOREACH(path, image_search_path[class]) { |
| _cleanup_closedir_ DIR *d = NULL; |
| struct dirent *de; |
| |
| d = opendir(path); |
| if (!d) { |
| if (errno == ENOENT) |
| continue; |
| |
| return -errno; |
| } |
| |
| FOREACH_DIRENT_ALL(de, d, return -errno) { |
| _cleanup_(image_unrefp) Image *image = NULL; |
| _cleanup_free_ char *truncated = NULL; |
| const char *pretty; |
| struct stat st; |
| |
| if (dot_or_dot_dot(de->d_name)) |
| continue; |
| |
| /* As mentioned above, we follow symlinks on this fstatat(), because we want to permit people |
| * to symlink block devices into the search path */ |
| if (fstatat(dirfd(d), de->d_name, &st, 0) < 0) { |
| if (errno == ENOENT) |
| continue; |
| |
| return -errno; |
| } |
| |
| if (S_ISREG(st.st_mode)) { |
| const char *e; |
| |
| e = endswith(de->d_name, ".raw"); |
| if (!e) |
| continue; |
| |
| truncated = strndup(de->d_name, e - de->d_name); |
| if (!truncated) |
| return -ENOMEM; |
| |
| pretty = truncated; |
| } else if (S_ISDIR(st.st_mode) || S_ISBLK(st.st_mode)) |
| pretty = de->d_name; |
| else |
| continue; |
| |
| if (!image_name_is_valid(pretty)) |
| continue; |
| |
| if (hashmap_contains(h, pretty)) |
| continue; |
| |
| r = image_make(pretty, dirfd(d), path, de->d_name, &st, &image); |
| if (IN_SET(r, -ENOENT, -EMEDIUMTYPE)) |
| continue; |
| if (r < 0) |
| return r; |
| |
| image->discoverable = true; |
| |
| r = hashmap_put(h, image->name, image); |
| if (r < 0) |
| return r; |
| |
| image = NULL; |
| } |
| } |
| |
| if (class == IMAGE_MACHINE && !hashmap_contains(h, ".host")) { |
| _cleanup_(image_unrefp) Image *image = NULL; |
| |
| r = image_make(".host", AT_FDCWD, NULL, "/", NULL, &image); |
| if (r < 0) |
| return r; |
| |
| image->discoverable = true; |
| |
| r = hashmap_put(h, image->name, image); |
| if (r < 0) |
| return r; |
| |
| image = NULL; |
| } |
| |
| return 0; |
| } |
| |
| int image_remove(Image *i) { |
| _cleanup_(release_lock_file) LockFile global_lock = LOCK_FILE_INIT, local_lock = LOCK_FILE_INIT; |
| _cleanup_strv_free_ char **settings = NULL; |
| _cleanup_free_ char *roothash = NULL; |
| char **j; |
| int r; |
| |
| assert(i); |
| |
| if (IMAGE_IS_VENDOR(i) || IMAGE_IS_HOST(i)) |
| return -EROFS; |
| |
| settings = image_settings_path(i); |
| if (!settings) |
| return -ENOMEM; |
| |
| roothash = image_roothash_path(i); |
| if (!roothash) |
| return -ENOMEM; |
| |
| /* Make sure we don't interfere with a running nspawn */ |
| r = image_path_lock(i->path, LOCK_EX|LOCK_NB, &global_lock, &local_lock); |
| if (r < 0) |
| return r; |
| |
| switch (i->type) { |
| |
| case IMAGE_SUBVOLUME: |
| |
| /* Let's unlink first, maybe it is a symlink? If that works we are happy. Otherwise, let's get out the |
| * big guns */ |
| if (unlink(i->path) < 0) { |
| r = btrfs_subvol_remove(i->path, BTRFS_REMOVE_RECURSIVE|BTRFS_REMOVE_QUOTA); |
| if (r < 0) |
| return r; |
| } |
| |
| break; |
| |
| case IMAGE_DIRECTORY: |
| /* Allow deletion of read-only directories */ |
| (void) chattr_path(i->path, 0, FS_IMMUTABLE_FL, NULL); |
| r = rm_rf(i->path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case IMAGE_BLOCK: |
| |
| /* If this is inside of /dev, then it's a real block device, hence let's not touch the device node |
| * itself (but let's remove the stuff stored alongside it). If it's anywhere else, let's try to unlink |
| * the thing (it's most likely a symlink after all). */ |
| |
| if (path_startswith(i->path, "/dev")) |
| break; |
| |
| _fallthrough_; |
| case IMAGE_RAW: |
| if (unlink(i->path) < 0) |
| return -errno; |
| break; |
| |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| STRV_FOREACH(j, settings) { |
| if (unlink(*j) < 0 && errno != ENOENT) |
| log_debug_errno(errno, "Failed to unlink %s, ignoring: %m", *j); |
| } |
| |
| if (unlink(roothash) < 0 && errno != ENOENT) |
| log_debug_errno(errno, "Failed to unlink %s, ignoring: %m", roothash); |
| |
| return 0; |
| } |
| |
| static int rename_auxiliary_file(const char *path, const char *new_name, const char *suffix) { |
| _cleanup_free_ char *rs = NULL; |
| const char *fn; |
| |
| fn = strjoina(new_name, suffix); |
| |
| rs = file_in_same_dir(path, fn); |
| if (!rs) |
| return -ENOMEM; |
| |
| return rename_noreplace(AT_FDCWD, path, AT_FDCWD, rs); |
| } |
| |
| int image_rename(Image *i, const char *new_name) { |
| _cleanup_(release_lock_file) LockFile global_lock = LOCK_FILE_INIT, local_lock = LOCK_FILE_INIT, name_lock = LOCK_FILE_INIT; |
| _cleanup_free_ char *new_path = NULL, *nn = NULL, *roothash = NULL; |
| _cleanup_strv_free_ char **settings = NULL; |
| unsigned file_attr = 0; |
| char **j; |
| int r; |
| |
| assert(i); |
| |
| if (!image_name_is_valid(new_name)) |
| return -EINVAL; |
| |
| if (IMAGE_IS_VENDOR(i) || IMAGE_IS_HOST(i)) |
| return -EROFS; |
| |
| settings = image_settings_path(i); |
| if (!settings) |
| return -ENOMEM; |
| |
| roothash = image_roothash_path(i); |
| if (!roothash) |
| return -ENOMEM; |
| |
| /* Make sure we don't interfere with a running nspawn */ |
| r = image_path_lock(i->path, LOCK_EX|LOCK_NB, &global_lock, &local_lock); |
| if (r < 0) |
| return r; |
| |
| /* Make sure nobody takes the new name, between the time we |
| * checked it is currently unused in all search paths, and the |
| * time we take possession of it */ |
| r = image_name_lock(new_name, LOCK_EX|LOCK_NB, &name_lock); |
| if (r < 0) |
| return r; |
| |
| r = image_find(IMAGE_MACHINE, new_name, NULL); |
| if (r >= 0) |
| return -EEXIST; |
| if (r != -ENOENT) |
| return r; |
| |
| switch (i->type) { |
| |
| case IMAGE_DIRECTORY: |
| /* Turn of the immutable bit while we rename the image, so that we can rename it */ |
| (void) read_attr_path(i->path, &file_attr); |
| |
| if (file_attr & FS_IMMUTABLE_FL) |
| (void) chattr_path(i->path, 0, FS_IMMUTABLE_FL, NULL); |
| |
| _fallthrough_; |
| case IMAGE_SUBVOLUME: |
| new_path = file_in_same_dir(i->path, new_name); |
| break; |
| |
| case IMAGE_BLOCK: |
| |
| /* Refuse renaming raw block devices in /dev, the names are picked by udev after all. */ |
| if (path_startswith(i->path, "/dev")) |
| return -EROFS; |
| |
| new_path = file_in_same_dir(i->path, new_name); |
| break; |
| |
| case IMAGE_RAW: { |
| const char *fn; |
| |
| fn = strjoina(new_name, ".raw"); |
| new_path = file_in_same_dir(i->path, fn); |
| break; |
| } |
| |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| if (!new_path) |
| return -ENOMEM; |
| |
| nn = strdup(new_name); |
| if (!nn) |
| return -ENOMEM; |
| |
| r = rename_noreplace(AT_FDCWD, i->path, AT_FDCWD, new_path); |
| if (r < 0) |
| return r; |
| |
| /* Restore the immutable bit, if it was set before */ |
| if (file_attr & FS_IMMUTABLE_FL) |
| (void) chattr_path(new_path, FS_IMMUTABLE_FL, FS_IMMUTABLE_FL, NULL); |
| |
| free_and_replace(i->path, new_path); |
| free_and_replace(i->name, nn); |
| |
| STRV_FOREACH(j, settings) { |
| r = rename_auxiliary_file(*j, new_name, ".nspawn"); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to rename settings file %s, ignoring: %m", *j); |
| } |
| |
| r = rename_auxiliary_file(roothash, new_name, ".roothash"); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to rename roothash file %s, ignoring: %m", roothash); |
| |
| return 0; |
| } |
| |
| static int clone_auxiliary_file(const char *path, const char *new_name, const char *suffix) { |
| _cleanup_free_ char *rs = NULL; |
| const char *fn; |
| |
| fn = strjoina(new_name, suffix); |
| |
| rs = file_in_same_dir(path, fn); |
| if (!rs) |
| return -ENOMEM; |
| |
| return copy_file_atomic(path, rs, 0664, 0, 0, COPY_REFLINK); |
| } |
| |
| int image_clone(Image *i, const char *new_name, bool read_only) { |
| _cleanup_(release_lock_file) LockFile name_lock = LOCK_FILE_INIT; |
| _cleanup_strv_free_ char **settings = NULL; |
| _cleanup_free_ char *roothash = NULL; |
| const char *new_path; |
| char **j; |
| int r; |
| |
| assert(i); |
| |
| if (!image_name_is_valid(new_name)) |
| return -EINVAL; |
| |
| settings = image_settings_path(i); |
| if (!settings) |
| return -ENOMEM; |
| |
| roothash = image_roothash_path(i); |
| if (!roothash) |
| return -ENOMEM; |
| |
| /* Make sure nobody takes the new name, between the time we |
| * checked it is currently unused in all search paths, and the |
| * time we take possession of it */ |
| r = image_name_lock(new_name, LOCK_EX|LOCK_NB, &name_lock); |
| if (r < 0) |
| return r; |
| |
| r = image_find(IMAGE_MACHINE, new_name, NULL); |
| if (r >= 0) |
| return -EEXIST; |
| if (r != -ENOENT) |
| return r; |
| |
| switch (i->type) { |
| |
| case IMAGE_SUBVOLUME: |
| case IMAGE_DIRECTORY: |
| /* If we can we'll always try to create a new btrfs subvolume here, even if the source is a plain |
| * directory. */ |
| |
| new_path = strjoina("/var/lib/machines/", new_name); |
| |
| r = btrfs_subvol_snapshot(i->path, new_path, |
| (read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) | |
| BTRFS_SNAPSHOT_FALLBACK_COPY | |
| BTRFS_SNAPSHOT_FALLBACK_DIRECTORY | |
| BTRFS_SNAPSHOT_FALLBACK_IMMUTABLE | |
| BTRFS_SNAPSHOT_RECURSIVE | |
| BTRFS_SNAPSHOT_QUOTA); |
| if (r >= 0) |
| /* Enable "subtree" quotas for the copy, if we didn't copy any quota from the source. */ |
| (void) btrfs_subvol_auto_qgroup(new_path, 0, true); |
| |
| break; |
| |
| case IMAGE_RAW: |
| new_path = strjoina("/var/lib/machines/", new_name, ".raw"); |
| |
| r = copy_file_atomic(i->path, new_path, read_only ? 0444 : 0644, FS_NOCOW_FL, FS_NOCOW_FL, COPY_REFLINK|COPY_CRTIME); |
| break; |
| |
| case IMAGE_BLOCK: |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| if (r < 0) |
| return r; |
| |
| STRV_FOREACH(j, settings) { |
| r = clone_auxiliary_file(*j, new_name, ".nspawn"); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to clone settings %s, ignoring: %m", *j); |
| } |
| |
| r = clone_auxiliary_file(roothash, new_name, ".roothash"); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to clone root hash file %s, ignoring: %m", roothash); |
| |
| return 0; |
| } |
| |
| int image_read_only(Image *i, bool b) { |
| _cleanup_(release_lock_file) LockFile global_lock = LOCK_FILE_INIT, local_lock = LOCK_FILE_INIT; |
| int r; |
| |
| assert(i); |
| |
| if (IMAGE_IS_VENDOR(i) || IMAGE_IS_HOST(i)) |
| return -EROFS; |
| |
| /* Make sure we don't interfere with a running nspawn */ |
| r = image_path_lock(i->path, LOCK_EX|LOCK_NB, &global_lock, &local_lock); |
| if (r < 0) |
| return r; |
| |
| switch (i->type) { |
| |
| case IMAGE_SUBVOLUME: |
| |
| /* Note that we set the flag only on the top-level |
| * subvolume of the image. */ |
| |
| r = btrfs_subvol_set_read_only(i->path, b); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case IMAGE_DIRECTORY: |
| /* For simple directory trees we cannot use the access |
| mode of the top-level directory, since it has an |
| effect on the container itself. However, we can |
| use the "immutable" flag, to at least make the |
| top-level directory read-only. It's not as good as |
| a read-only subvolume, but at least something, and |
| we can read the value back. */ |
| |
| r = chattr_path(i->path, b ? FS_IMMUTABLE_FL : 0, FS_IMMUTABLE_FL, NULL); |
| if (r < 0) |
| return r; |
| |
| break; |
| |
| case IMAGE_RAW: { |
| struct stat st; |
| |
| if (stat(i->path, &st) < 0) |
| return -errno; |
| |
| if (chmod(i->path, (st.st_mode & 0444) | (b ? 0000 : 0200)) < 0) |
| return -errno; |
| |
| /* If the images is now read-only, it's a good time to |
| * defrag it, given that no write patterns will |
| * fragment it again. */ |
| if (b) |
| (void) btrfs_defrag(i->path); |
| break; |
| } |
| |
| case IMAGE_BLOCK: { |
| _cleanup_close_ int fd = -1; |
| struct stat st; |
| int state = b; |
| |
| fd = open(i->path, O_CLOEXEC|O_RDONLY|O_NONBLOCK|O_NOCTTY); |
| if (fd < 0) |
| return -errno; |
| |
| if (fstat(fd, &st) < 0) |
| return -errno; |
| if (!S_ISBLK(st.st_mode)) |
| return -ENOTTY; |
| |
| if (ioctl(fd, BLKROSET, &state) < 0) |
| return -errno; |
| |
| break; |
| } |
| |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| return 0; |
| } |
| |
| int image_path_lock(const char *path, int operation, LockFile *global, LockFile *local) { |
| _cleanup_free_ char *p = NULL; |
| LockFile t = LOCK_FILE_INIT; |
| struct stat st; |
| bool exclusive; |
| int r; |
| |
| assert(path); |
| assert(global); |
| assert(local); |
| |
| /* Locks an image path. This actually creates two locks: one "local" one, next to the image path |
| * itself, which might be shared via NFS. And another "global" one, in /run, that uses the |
| * device/inode number. This has the benefit that we can even lock a tree that is a mount point, |
| * correctly. */ |
| |
| if (!path_is_absolute(path)) |
| return -EINVAL; |
| |
| switch (operation & (LOCK_SH|LOCK_EX)) { |
| case LOCK_SH: |
| exclusive = false; |
| break; |
| case LOCK_EX: |
| exclusive = true; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| if (getenv_bool("SYSTEMD_NSPAWN_LOCK") == 0) { |
| *local = *global = (LockFile) LOCK_FILE_INIT; |
| return 0; |
| } |
| |
| /* Prohibit taking exclusive locks on the host image. We can't allow this, since we ourselves are |
| * running off it after all, and we don't want any images to manipulate the host image. We make an |
| * exception for shared locks however: we allow those (and make them NOPs since there's no point in |
| * taking them if there can't be exclusive locks). Strictly speaking these are questionable as well, |
| * since it means changes made to the host might propagate to the container as they happen (and a |
| * shared lock kinda suggests that no changes happen at all while it is in place), but it's too |
| * useful not to allow read-only containers off the host root, hence let's support this, and trust |
| * the user to do the right thing with this. */ |
| if (path_equal(path, "/")) { |
| if (exclusive) |
| return -EBUSY; |
| |
| *local = *global = (LockFile) LOCK_FILE_INIT; |
| return 0; |
| } |
| |
| if (stat(path, &st) >= 0) { |
| if (S_ISBLK(st.st_mode)) |
| r = asprintf(&p, "/run/systemd/nspawn/locks/block-%u:%u", major(st.st_rdev), minor(st.st_rdev)); |
| else if (S_ISDIR(st.st_mode) || S_ISREG(st.st_mode)) |
| r = asprintf(&p, "/run/systemd/nspawn/locks/inode-%lu:%lu", (unsigned long) st.st_dev, (unsigned long) st.st_ino); |
| else |
| return -ENOTTY; |
| |
| if (r < 0) |
| return -ENOMEM; |
| } |
| |
| /* For block devices we don't need the "local" lock, as the major/minor lock above should be |
| * sufficient, since block devices are host local anyway. */ |
| if (!path_startswith(path, "/dev/")) { |
| r = make_lock_file_for(path, operation, &t); |
| if (r < 0) { |
| if (!exclusive && r == -EROFS) |
| log_debug_errno(r, "Failed to create shared lock for '%s', ignoring: %m", path); |
| else |
| return r; |
| } |
| } |
| |
| if (p) { |
| (void) mkdir_p("/run/systemd/nspawn/locks", 0700); |
| |
| r = make_lock_file(p, operation, global); |
| if (r < 0) { |
| release_lock_file(&t); |
| return r; |
| } |
| } else |
| *global = (LockFile) LOCK_FILE_INIT; |
| |
| *local = t; |
| return 0; |
| } |
| |
| int image_set_limit(Image *i, uint64_t referenced_max) { |
| assert(i); |
| |
| if (IMAGE_IS_VENDOR(i) || IMAGE_IS_HOST(i)) |
| return -EROFS; |
| |
| if (i->type != IMAGE_SUBVOLUME) |
| return -EOPNOTSUPP; |
| |
| /* We set the quota both for the subvolume as well as for the |
| * subtree. The latter is mostly for historical reasons, since |
| * we didn't use to have a concept of subtree quota, and hence |
| * only modified the subvolume quota. */ |
| |
| (void) btrfs_qgroup_set_limit(i->path, 0, referenced_max); |
| (void) btrfs_subvol_auto_qgroup(i->path, 0, true); |
| return btrfs_subvol_set_subtree_quota_limit(i->path, 0, referenced_max); |
| } |
| |
| int image_read_metadata(Image *i) { |
| _cleanup_(release_lock_file) LockFile global_lock = LOCK_FILE_INIT, local_lock = LOCK_FILE_INIT; |
| int r; |
| |
| assert(i); |
| |
| r = image_path_lock(i->path, LOCK_SH|LOCK_NB, &global_lock, &local_lock); |
| if (r < 0) |
| return r; |
| |
| switch (i->type) { |
| |
| case IMAGE_SUBVOLUME: |
| case IMAGE_DIRECTORY: { |
| _cleanup_strv_free_ char **machine_info = NULL, **os_release = NULL; |
| sd_id128_t machine_id = SD_ID128_NULL; |
| _cleanup_free_ char *hostname = NULL; |
| _cleanup_free_ char *path = NULL; |
| |
| r = chase_symlinks("/etc/hostname", i->path, CHASE_PREFIX_ROOT|CHASE_TRAIL_SLASH, &path, NULL); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to chase /etc/hostname in image %s: %m", i->name); |
| else if (r >= 0) { |
| r = read_etc_hostname(path, &hostname); |
| if (r < 0) |
| log_debug_errno(errno, "Failed to read /etc/hostname of image %s: %m", i->name); |
| } |
| |
| path = mfree(path); |
| |
| r = chase_symlinks("/etc/machine-id", i->path, CHASE_PREFIX_ROOT|CHASE_TRAIL_SLASH, &path, NULL); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to chase /etc/machine-id in image %s: %m", i->name); |
| else if (r >= 0) { |
| _cleanup_close_ int fd = -1; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY); |
| if (fd < 0) |
| log_debug_errno(errno, "Failed to open %s: %m", path); |
| else { |
| r = id128_read_fd(fd, ID128_PLAIN, &machine_id); |
| if (r < 0) |
| log_debug_errno(r, "Image %s contains invalid machine ID.", i->name); |
| } |
| } |
| |
| path = mfree(path); |
| |
| r = chase_symlinks("/etc/machine-info", i->path, CHASE_PREFIX_ROOT|CHASE_TRAIL_SLASH, &path, NULL); |
| if (r < 0 && r != -ENOENT) |
| log_debug_errno(r, "Failed to chase /etc/machine-info in image %s: %m", i->name); |
| else if (r >= 0) { |
| r = load_env_file_pairs(NULL, path, &machine_info); |
| if (r < 0) |
| log_debug_errno(r, "Failed to parse machine-info data of %s: %m", i->name); |
| } |
| |
| r = load_os_release_pairs(i->path, &os_release); |
| if (r < 0) |
| log_debug_errno(r, "Failed to read os-release in image, ignoring: %m"); |
| |
| free_and_replace(i->hostname, hostname); |
| i->machine_id = machine_id; |
| strv_free_and_replace(i->machine_info, machine_info); |
| strv_free_and_replace(i->os_release, os_release); |
| |
| break; |
| } |
| |
| case IMAGE_RAW: |
| case IMAGE_BLOCK: { |
| _cleanup_(loop_device_unrefp) LoopDevice *d = NULL; |
| _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL; |
| |
| r = loop_device_make_by_path(i->path, O_RDONLY, LO_FLAGS_PARTSCAN, &d); |
| if (r < 0) |
| return r; |
| |
| r = dissect_image(d->fd, NULL, NULL, DISSECT_IMAGE_REQUIRE_ROOT|DISSECT_IMAGE_RELAX_VAR_CHECK, &m); |
| if (r < 0) |
| return r; |
| |
| r = dissected_image_acquire_metadata(m); |
| if (r < 0) |
| return r; |
| |
| free_and_replace(i->hostname, m->hostname); |
| i->machine_id = m->machine_id; |
| strv_free_and_replace(i->machine_info, m->machine_info); |
| strv_free_and_replace(i->os_release, m->os_release); |
| |
| break; |
| } |
| |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| i->metadata_valid = true; |
| |
| return 0; |
| } |
| |
| int image_name_lock(const char *name, int operation, LockFile *ret) { |
| assert(name); |
| assert(ret); |
| |
| /* Locks an image name, regardless of the precise path used. */ |
| |
| if (!image_name_is_valid(name)) |
| return -EINVAL; |
| |
| if (getenv_bool("SYSTEMD_NSPAWN_LOCK") == 0) { |
| *ret = (LockFile) LOCK_FILE_INIT; |
| return 0; |
| } |
| |
| if (streq(name, ".host")) |
| return -EBUSY; |
| |
| const char *p = strjoina("/run/systemd/nspawn/locks/name-", name); |
| (void) mkdir_p("/run/systemd/nspawn/locks", 0700); |
| return make_lock_file(p, operation, ret); |
| } |
| |
| bool image_name_is_valid(const char *s) { |
| if (!filename_is_valid(s)) |
| return false; |
| |
| if (string_has_cc(s, NULL)) |
| return false; |
| |
| if (!utf8_is_valid(s)) |
| return false; |
| |
| /* Temporary files for atomically creating new files */ |
| if (startswith(s, ".#")) |
| return false; |
| |
| return true; |
| } |
| |
| bool image_in_search_path(ImageClass class, const char *image) { |
| const char *path; |
| |
| assert(image); |
| |
| NULSTR_FOREACH(path, image_search_path[class]) { |
| const char *p; |
| size_t k; |
| |
| p = path_startswith(image, path); |
| if (!p) |
| continue; |
| |
| /* Make sure there's a filename following */ |
| k = strcspn(p, "/"); |
| if (k == 0) |
| continue; |
| |
| p += k; |
| |
| /* Accept trailing slashes */ |
| if (p[strspn(p, "/")] == 0) |
| return true; |
| |
| } |
| |
| return false; |
| } |
| |
| static const char* const image_type_table[_IMAGE_TYPE_MAX] = { |
| [IMAGE_DIRECTORY] = "directory", |
| [IMAGE_SUBVOLUME] = "subvolume", |
| [IMAGE_RAW] = "raw", |
| [IMAGE_BLOCK] = "block", |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP(image_type, ImageType); |